1. Field of the Invention
The invention relates in general to panel joints, and more specifically to panel joints for joining two upstanding panel members at right angles to one another.
2. Description of the Prior Art
It is well known in the art to join two panel members via a right angle joining member having slots in one leg portion which cooperate with screws fixed to the panel members. U.S. Pat. Nos. 1,889,753 and 2,490,018 and U.K Pat. No. 265,089 disclose examples of such panel joints.
With the joint constructions set forth in these patents, the screws need not be advanced to their final positions until the joining member has been vertically advanced to its final position. Thus, sufficient spacing between the head of the screw and the associated panel may be maintained to accomodate any bow or out-of-flatness in the panels. Once the joining member is advanced to its final position, the screws are tightened to maintain the assembly. This prior art arrangement is suitable when the screws are accessible after the panel members are joined, so that they may be securely tightened.
In certain applications, however, the panel members to be joined form a room or cubicle, and it is essential that the joining hardware be concealed. Thus, the joining hardware must be applied to the back sides of the panels, i.e., those surfaces outside the cubicle. Further, these applications require the room or cubicle to be assembled within a space which denies access to the back sides of the panel, once they are placed in upstanding adjacent positions preparatory to the joining step. An example of such an application is the assembly of a wood, or non-metal, elevator cab on a platform in the hatch or hoistway of a building. The panels which form the cab are located about one inch from the sides of the platform, and the platform is so close to the walls of the hoistway that an assembler would find it difficult or impossible to work between the panels and the hoistway walls. Typical spacings between the platform and hoistway walls are two inches between the platform and the front and back walls, and eight inches between the platform and the side walls.
Panel members used to form an elevator cab, for example, are relatively thick and heavy, and their surfaces may not be perfectly flat. The weight and non-flatness add to the problem of assembling such panels with tight joints in a restricted space where the back sides of the panels are not directly accessible to the assembler.
The joints between the panel members must be tight along the complete length of the joint. Further, the joint must stay tight during usage of the cubicle or room, even when the cubicle is subjected to movement, such as in the hereinbefore mentioned elevator cab application.
It would thus be desirable to provide a new and improved panel joint for relatively large, heavy panels which enables the panels to be quickly and tightly joined with the desired vertical orientation of the panel surfaces. It would further be desirable to remove or reduce any bow or out-of-flatness condition of the panel members, if these objectives can be achieved without increasing assembly time. Still further, since the panels may be required to be assembled in locations which have very little space adjacent to the back sides of the panels, the joining member must be such that it does not require access to the back sides of the panel members.